Dross remover



Jan. 18, 1955 J. T. SIEFERTQSR 2,699,933

DROSS REMOVER Filed Oct. 28, 1952 @www United States Patent DROSSREMOVER .lohn T. Siefert, Sr., Los Angeles, Calif., assignor to NorthropAircraft, nc., Hawthorne, Calif., a corporation of CaliforniaApplication October 28, 1952, Serial No. 317,280

3 Claims. (Cl. 266-37) My invention relates to the lield of skimmers andthe like and more particularly to dross removers.

In the preparation of pig lead it has been found necessary to introducecertain impurities into the molten mixture in order to drive out noxiousgases as well as to aid in the removal of other undesirable elementsthrough the medium of a chemical reaction or combination. Not all of theimpurities are removed from the molten mixture at the time the lead ismade into pigs. The pigs are transported, stored and subsequentlyremelted for purification, alloying, casting into final shapes, or intoingots for rolling. During the remelting process a layer of the moltenmixture, similar to slag in appearance but composed of metallic oxides,appears on the surface. This layer must be removed from the molten metalbefore the metal can be prepared for its intended use. At present thedevices used in removing dross have been unsuccessful in eliminating thelarge losses of molten lead which adheres to the skimmer or the drossretained by the dross remover during the skimming and removing process.

It is, therefore, the object of this invention to greatly minimize theloss of the molten lead in the dross removal process. This has beeneffected by designing a skimming device which is devoid of uppermostflat surfaces upon which the molten metal might form globules and thusbe retained and consequently removed from the molten solution. Insteadof providing the aforementioned flat surfaces, my device has a grid oftriangular elements positioned apex upward from which the molten metalslides back into the pot containing the solution, thus precluding anyadhesion of the molten metal to the rid. g For a complete disclosure ofthe invention, a detailed description thereof will now be given inconnection with the accompanying drawings forming a part of thespecication, wherein:

Figure l is a plan view of the dross remover.

Figure 2 is a cross-sectional view of the dross remover along the line2-2 in Figure l.

Figure 3 is a cross-sectional view of the dross remover along the line3--3 in Figure 1.

Referring to the drawings, in which similar reference charactersdesignate corresponding parts, the grid is of generally rectangularshape, having opposite faces one of which is concave, and is composed oftriangular shaped bars 1 equally spaced on top 2 and bottom 3 and heldtogether by a frame 4 to which a handle 5 is attached. The sides 6 ofthe frame are bowed outwardly as is the front side 7, the side 8attached to the handle is straight. The grid as a whole is boweddownwardly as indicated by numeral 9 and thus the innermost or centerbar 10 is the most bowed or lowermost when viewing the dross removerfrom the side. The slope of the sides 6a, of the two side bars 6, isless, at the mid point, then that "ice of the grid members or bars andgradually increases, as it approaches the ends, until, at that point, itis steeper than the grid bars, the bottom spacing 3 remaining constant.The inner portion of the front 11 and back 12 sides slopes inwardly asshown. The frame 4 is rounded on all corners to eliminate sharp edges.

My invention operates as follows: The dross is swept up into the gridwork and there retained due to the basketlike shape which the removerhas because of its generally bowed configuration. Any molten metal whichis taken in with the sweep of the skimmer readily gravitates through thespacing at the bottom 3. The basket-like configuration allows theoperator to jar the skimmer on the side of the container holding themolten metal, thus further ridding the dross of any remaining metal andstill keeping the dross within the remover.

While in order to comply with the statute, the invention has beendescribed in language more or less specic as to structural features, itis to be understood that the invention is not limited to the specificfeatures shown, but that the means and construction herein disclosedcomprises a preferred form of putting the invention into effect, and theinvention is therefore claimed in any of its forms or modificationswithin the legitimate and valid scope of the appended claims.

What is claimed is:

1. An implement for skimming dross from molten metal comprising: agenerally rectangular grid having opposite faces, one of which isconcave, and comprising a series of laterally spaced, generally parallelbars, each having a sharp longitudinally extending edge lying in asurface dening the concave side of said grid, each pair of opposed sidesurfaces of adjacent bars converging from the said sharp edges of saidadjacent bars toward the other face of said grid and forming edges atsaid other face that are uniformly spaced throughout the length of saidbars for drainage of molten metal therebetween, the end bars of saidseries having side surfaces which diverge from the said sharp edgesthereof towards said other grid face, and cross bars connecting the endsof said parallel bars, said cross bars having sharp longitudinallyextendlng edges on the concave face of said grid with side surfaceswhich diverge therefrom toward said other grid ace.

2. An implement for skimming dross from molten metal comprises: agenerally rectangular grid having opposite faces, one of which isconcave, and' comprising a series of generally parallel, uniformlylaterally spaced bars, and cross bars connecting the ends of saidparallel bars, each of said bars being generally triangular intransverse section and presenting a sharp longitudinal edge to theconcave face of said grid with side surfaces that diverge toward theother face of said grid.

3. The structure delined in claim 2,4 in which the end bars of theseries and the cross bars comprise a generally rectangular frame havingrounded corners with the sharp edges of said end and creas barsconstituting continuations of each other.

References Cited in the le of this patent UNITED STATES PATENTS 87,385Winchester Mar. 2, 1869 703,683 Vrooman et al. July l, 1902 1,760,510Marvel May 27, 1930 1,786,973 Webber Dec. 30, 1930 FOREIGN PATENTS980,836 France Ian. 3. 195.1

